2004 PORSCHE 911 TURBO Information Manual

· 22 ·
provide effective protection
against stone chips.
Elegantly matched to the exterior
of the car is the all-new wheel
design. The 19-inch forged alloys
have a standard two-tone finish
as well as wide, low-profile tyres.
The standard tyre dimensions
are 235/35 ZR 19 (front) and
305/30 ZR 19 (rear).
The interior of the car is equally
compelling and entirely designed
around the driver. The high-quality
surfaces include a full leather
finish on the standard electric
seats as well as the dashboard,
doors and rear side panels. Two
sports seat options are also
available, one featuring adaptive
adjustment. The standard
equipment package includes a
new gear-knob design – created
exclusively for the 911 Turbo –
· 21 ·The new 911 Turbo |
The new 911 Turbo
The extreme capability of the new
911 Turbo is elegantly enclosed in
a highly distinctive exterior. While
signalling the unique athleticism of
the car, it remains unmistakably 911.
The aerodynamics are exceptionally
well balanced, with positive
downforce at the rear. The drag
coefficient is remarkably low
at just 0.31. With its streamlined
shape and lightweight build,
the new 911 Turbo offers excellent
fuel economy as well as super-
lative performance.The standard Bi-Xenon headlights
with integral cleaning system
are compact, stylish and elegantly
incorporated within the new
front-end design. The front apron
moulding is an entirely new
development, featuring high-
performance LED indicators in
the outer air intake ducts. The
compact front foglights are
neatly positioned on the outer
edges of the front apron.
The side air intakes, to the rear
of the doors, provide optimum air
delivery to the twin intercoolerunits. Equally efficient are the
cooling air ducts to the front and
rear brake assemblies. This
enhanced cooling action is an
important factor in the excellent
performance of the standard
braking system.
The body of the car is much wider
across the rear than the front. A
generous wheel track is combined
with wider tyres to achieve
enormous lateral grip. The engine
lid is another totally new design
and features an integral bi-plane
rear spoiler. The
upper wing
element is automatically
raised at
approximately 120 km / h (75 mph)
and lowered at around 60 km / h
(37 mph).
The rear apron moulding has also
been redesigned to blend with
the rest of the car. The side air
outlets and fully enclosed twin
tailpipes are a further indication of
the power within. Black plastic
sills along the sides of the body
· 20 ·
Some say power is all about muscle.
For us, it starts with the mind.
Drive
Poised for action, yet always relaxed.
Designing the new 911 Turbo.
Rear wing retracted
Rear wing deployed
and a three-spoke sports steering
wheel featuring 40 mm of height
and reach adjustment.
The overall design of the
new 911 Turbo marks another
new phase in the ongoing
evolution of this remarkable car.
Wholly integral to the fundamental
vehicle concept, every detail
is a direct expression of power,
composure and comfort.

· 26 ·The new 911 Turbo |
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· 25 · · 24 · · 23 ·
7. Exhaust-gas turbocharger
with Variable Turbine
Geometry (VTG)
8. Intercoolers
9. Pressure pipe
10. Throttle valve
(electronically actuated)
11. Exhaust system
12. Oil filter
13. Engine oil reservoir
(dry-sump lubrication)
1. Radiator module (left)
2. Radiator module (centre)
3. Radiator module (right)
4. Coolant pipe
5. Coolant expansion tank
6. Air filter
14. Generator
15. PASM damper
16. Tandem brake booster
17. 6-speed manual gearbox
18. Front differential
19. Fuel tank1. Oil scavenge pump
2. Oil-pressure pump (obscured)
3. Engine oil reservoir
(dry-sump lubrication)
4. Camshaft adjuster (VarioCam Plus)
5. Intake camshaft
6. Tappets (with hydraulic valve
clearance adjustment)
7. Valve springs
8. Intake valves
9. Nikasil-coated cylinder bore
10. Forged aluminium piston
11. Forged connecting rod
12. Crankshaft
13. Camshaft drive chain
14. Camshaft drive chain tensioner
with guide rail
15. Single-spark ignition coil
16. Spark plug
17. Exhaust-gas turbocharger with
Variable Turbine Geometry (VTG)
18. Exhaust system
19. Catalytic converter
20. Pressure pipe
21. Throttle valve (electronically actuated)
22. Plenum chamber
23. Ancillary drive belt
24. Fluid reservoir for
power-steering system
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4
5
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2019
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6
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14
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7810
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6
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8

Tiptronic S, the new 911 Turbo
requires just 3.7 seconds to
reach 100 km / h (62 mph), and
just 12.2 seconds for 200 km / h
(124 mph). Facilitating this
performance is the additionaltraction provided by the new
electronically controlled all-wheel
drive system (see page 48).
In appropriate track conditions,
the car’s maximum speed is
310 km / h (193 mph).
· 29 ·The new 911 Turbo |
Drive
Every 911 shares the same
fundamental engine charac-
teristics. Key among these are
the ‘flat-six’ cylinder layout
and rear-mounted installation.
There is, however, one essential
feature that is unique to the
911 Turbo. The twin turbocharger
system that gives the car its name
now includes Variable Turbine
Geometry (see page 32). Thus
equipped, the 3.6-litre engine
develops 353 kW (480 bhp) at6,000 rpm. Weighing 1,585 kg,
the standard 911 Turbo (with
manual gearbox) has an excellent
power-to-weight ratio of
302.8 bhp per tonne. Specific
power output is 133 bhp per
litre of engine displacement.
Maximum torque is a phenomenal
620 Nm, rising to 680 Nm with
the overboost function in the
optional Sport Chrono Package
Turbo (see page 60). Thanks
to VarioCam Plus (see page 38)and the new turbocharger system,
all of that torque is fully available
between 1,950 and 5,000 rpm.
The resulting acceleration is
inspirationally quick. Equipped with
· 28 · · 27 ·The new 911 Turbo |
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Engine.
Heart and soul of the new 911 Turbo.
911 Turbo engine

Lightweight design.
The six-cylinder boxer engine is
a highly compact unit offering
excellent cylinder charging and
torque characteristics as well
as optimum balance and minimal
vibration. With the cylinders
arranged horizontally on either
side of the crankshaft, the
layout is key to the car’s low
centre of gravity.
The alloy crankcase consists
of two main sections, each
containing one bank of cylinders.
The crankshaft runs in eight main
bearings and is driven by forged
connecting rods. For optimum
durability, we’ve used forged
aluminium pistons running in
Nikasil-coated aluminium liners
and featuring individual oil-spray
cooling. Key benefits include lower
frictional resistance and longer
service life.
The cylinder heads are made
from a lightweight alloy which
is extremely resistant to high
temperature. Each bank of
cylinders has two overhead
camshafts driving a set of four
valves – two inlet and two exhaust
– on each individual cylinder.
The valves are arranged in a ‘V’
configuration and feature a highly
efficient dual-spring design.
Engine performance is further
enhanced with the aid of bothVariable Turbine Geometry (VTG –
see page 32) and VarioCam Plus
(variable valve timing and lift
on inlet side – see page 38). The
benefits are not only greater
power and torque, but also better
fuel economy and lower emissions.
Dry-sump lubrication.
This classic dry-sump system
with separate oil reservoir
ensures consistent oil pressures
throughout the engine. In doing
so, it compensates for even the
most extreme and prolonged
gravitational loads.
After passing through the engine,
every drop of oil is returned
directly to the external reservoir.
The flow is driven by two pairs of
scavenge pumps in the cylinder
heads and a further two pumps in
the crankcase. Gas is removed
from the returning oil by means of
a defoaming device in the
reservoir. As a result, the oil
level in the reservoir remains
virtually constant at all times.
The oil is returned to the
lubrication points in the engine
by means of a dedicated
oil-feed pump. With a further
scavenge pump in each of the
twin turbocharger units, the
new 911 Turbo has a total of nineseparate pumps to drive the
lubrication system.
The oil level can be checked from
inside the car via the standard
on-board computer. This solution
is not only cleaner and more
convenient than a conventional
dipstick, it is also significantly
more accurate.
· 30 ·· 31 ·The new 911 Turbo |
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Main rotating assembly and valve gear

vanes are opened further. By
varying the vane angle, it is
possible to achieve the required
boost pressure over the entire
engine speed range. As a result,
there is no need for excess-
pressure valves as found on
conventional turbocharged
engines.
· 34 · · 32 ·· 33 ·The new 911 Turbo |
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Variable Turbine Geometry (VTG).
Creating the optimum turbo for every scenario.
known as ‘turbo lag’, means there
is virtually no turbocharging effect
at lower engine speeds. To
overcome this problem, the twin
water-cooled turbochargers on
the new 911 Turbo feature Variable
Turbine Geometry (VTG). With
this technology, the gas-flow from
the engine is channelled onto Larger turbo units, which create
lower back-pressure at higher rpm,
take considerably longer to spin
up under power due to the large
cross-sectional area and relative
inertia of the heavier turbine.
Generally, this type of turbo will
only be effective in the medium
rpm range. This phenomenon,
Turbocharger guide vane adjuster Turbocharger with Variable Turbine Geometry (VTG)
up easily to its optimum speed.
The key disadvantage of using
a smaller turbo is that the back-
pressure generated at higher
engine speeds causes a significant
reduction in performance.
Resistance is caused by the smaller
cross-sectional area through which
the exhaust is required to flow.
The 911 Turbo has always been
synonymous with performance.
Now the car is more capable than
ever thanks to a new twin turbo
system featuring Variable Turbine
Geometry (VTG).
On a conventional turbocharger,
the exhaust flow drives a turbine
that is connected to a compressor
in the air intake tract. By ‘squeezing’
the incoming air, the amount
of oxygen in a given volume isincreased. Since compression also
causes an increase in temperature,
the air must be passed through
an ‘intercooler’ unit. With more
oxygen present in each cylinder
charge, more fuel can be burnt
yielding greater energy. Since
higher exhaust pressures generate
corresponding loads on the intake
side, the intake pressure must
be carefully controlled in order
to protect the engine. On the new
911 Turbo, the ‘boost pressure’ islimited using ‘wastegate’ valves
that bypass excess pressure
around the twin exhaust turbines.
Another important factor is the
size of the turbo unit. Since a
smaller turbine has a lower mass,
it generally responds more quickly
to increasing pressure, spinning
the turbines via electronically
adjustable guide vanes. By
changing the vane angle, the
system can replicate the
geometry in all types of turbo,
large or small.
With Variable Turbine Geometry
(VTG), it is possible to achieve
higher turbine speeds, and thus
higher boost pressure, at lower
engine rpm. Cylinder charging issignificantly improved, with a
corresponding increase in both
power and torque. Maximum
torque is reached at lower rpm
and is retained across a wider rev
range. A full 620 Nm is available
from as low as 1,950 rpm up to
5,000 rpm. Every throttle input is
met with exceptional response
and phenomenal acceleration.
When the boost pressure reaches
its maximum value, the guide

· 36 · · 35 ·· 37 ·The new 911 Turbo |
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Guide vanes open Guide vanes closedGuide vanes open Guide vanes closed
The capability of the engine can
be further enhanced by selecting
‘Sport’ mode on the optional Sport
Chrono Package Turbo (see page
60). Under full acceleration, the
boost is temporarily increased by
approximately 0.2 bar. During this
phase, the engine develops as
much as 60 Nm of additional
torque.
Matching the superlative
performance of the car is the
efficiency with which it is
generated. In spite of the increase
in power and torque, the new
911 Turbo offers a further
reduction in fuel consumption.
1
2
3
4
5
6
7
8
9
10
1. Turbine casing
2. Movable guide vanes
3. Turbine wheel4. Electric motor for guide
vane adjustment
5. Guide vane adjuster
6. Compressor casing7. Compressor wheel
8. Excess-pressure valve
9. Oil inlet
10. Coolant inlet340 500 540
580
620 660 700
220 240
260
280
300
1500
7500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000
380 420
460
1000
Power (kW)
Engine speed (rpm)
620 Nm
120 140
160
180
200
Torque (Nm)
680 Nm
740 320
340 360380780 820860
353 kW (480 bhp)
911 Turbo
911 Turbo overboost

locked, the outermost ring –
which is driven by two large
profile cams – is in direct contact
with the valve. When the pin is
removed, the innermost lifter –
operated by a smaller cam
lobe – has sole influence over the
amount of valve lift. The timing of
each valve is steplessly controlled
by means of an electro-hydraulic
rotary vane adjuster at the head
of the corresponding camshaft.To improve responsiveness
during warm-up in cold weather,
VarioCam Plus will select the
higher valve lift setting and retard
valve timing.
At medium revs and low engine
loads, the lower valve lift setting
is selected and timing advanced in
order to reduce fuel consumption
and emissions. The economy of
the engine is particularly
enhanced at lower engine speeds.
For maximum power and torque,
the higher lift setting is selected
and the timing of the valves is
advanced.
From the driver’s perspective, the
results are clear: copious torque
with exceptional fuel economy,
particularly in comparison with
much larger yet similarly rated
engines.
· 39 ·The new 911 Turbo |
Drive
VarioCam Plus combines variable
valve timing with two-stage valve
lift on each inlet camshaft. The
resulting benefits include greater
power and torque at all engine
speeds, as well as smoother
running, better fuel economy and
fewer exhaust emissions.Essentially, VarioCam Plus offers
two engines in one. The first is
designed for normal road driving,
the second for high-performance
use. The system switches
seamlessly between the two
as driver inputs change. All
operations are centrally controlled
by the engine management
system. The result: emphaticacceleration and smoother
running.
The two-stage lift mechanism on
each inlet valve consists of an
electro-hydraulically switchable
tappet. Each of the 12 tappets
has two concentric lifters which
can be locked together by means
of a pin. When the tappets are
· 38 ·
VarioCam Plus.
Optimum valve timing, optimum valve lift, in all load conditions.

Engine cooling.
The 911 Turbo engine features
cross-flow water cooling with fully
integrated coolant management.
This technology ensures a
consistent flow of coolant to each
of the engine’s cylinders. All
coolant passages are integral to
the block, thus eliminating the
need for external hoses. Each
cylinder receives a fresh supply
of coolant which has not been
pre-warmed by the engine. As well
as improving reliability, this
helps to minimise maintenance
requirements. Waste heat from
the oil is transferred to the
coolant via two oil/water heat
exchangers. The coolant is routed
through twin radiator modules
ahead of the front wheels and a
centrally placed unit in the nose.
Engine management.
Optimum performance is assured
at all times with the aid of
the Motronic ME7.8.1 engine
management system. On the new
911 Turbo, this powerful ECU is
responsible for all engine-related
functions and assemblies (see
diagram). Key among these are
the Variable Turbine Geometry
(VTG), VarioCam Plus and
electronic throttle system – one
of the essential prerequisites
for the standard Porsche Stability
Management (PSM). The results:
optimum economy, emissions
and performance, regardless of
driving style.Another important task performed
by the engine management
system is cylinder-specific knock
control. By preventing pre-ignition
at high engine speeds, this
function can avert costly damage
to the pistons and cylinders. Since
temperatures tend to vary in
different parts of the engine, each
cylinder is monitored separately.
If a risk is detected, the individual
ignition timing is adjusted.
The EU-compliant on-board
diagnostics system provides
continuous fault detection and
early warning for the exhaust
and fuel supply systems. The
resulting benefits are active
prevention of harmful emissions
as well as consistent rates of
fuel consumption.
· 40 ·· 41 ·The new 911 Turbo |
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Input data Used to regulate /control
Engine management system
(Motronic ME7.8.1)
Engine load
Pressure upstream from throttle
Throttle-valve angle
Engine speed (from crankshaft)
Camshaft phase angles
Throttle-pedal position
Lambda signal
Knock sensor signal
Ignition
Fuel injection
Throttle valve
Heating elements in lambda sensors
Fuel pump
Fuel-tank venting
CAN interface to
all-wheel drive control unit CAN interface to transmissionMoment interface to Porsche
Stability Management (PSM)
VarioCam Plus
– camshaft phase angle
– valve lift control
Electronic controller for
Variable Turbine Geometry (VTG)
Bypass valve
Secondary air injection
Engine-bay fan
Starter
On-board diagnostics
Air-conditioning compressor
Interface to instrument cluster
Radiator fans
Vehicle speed
Air-conditioning settings
Engine immobiliser status
Clutch pedal switch
Ambient air pressure
Temperatures
– coolant
– airflow upstream from throttle
– engine oil
– air in engine compartment
– ambient air
Exhaust-gas temperature